The availability of shared storage systems for electronic documents has increased the ability of computer end users to share and collaborate in the creation of a variety of electronic documents. End users can cause electronic documents to be stored in shared storage systems on a computer network, such as the internet. End users can instruct such a shared storage system to allow electronic documents to be shared with other end users of the shared storage system. A shared storage system generally has an access control component in a file system that tracks the access rights users have for each electronic document. In many typical end user scenarios, an end user may create and store an electronic document in local storage on an end user computer, and then upload the electronic document to the shared storage system. Storing the electronic document in a shared storage system can be accomplished on the end user computer, for example, by using a “save as” operation of an application, or a file move or copy operation of a file system, or an upload operation of a client application of the shared storage system, to store the electronic document directly in the shared storage system or in a directory of the end user computer file system which is synchronized with the shared storage system.
After an electronic document has been shared with two or more end users, the shared storage system manages access to the shared electronic document to ensure consistency of the electronic document, especially in the case of collaborative modifications to the electronic document. A kind of collaboration system, typically resident on a server computer that is configured to access the file system of the shared storage system, typically is involved in managing this collaborative modification by tracking which users currently are accessing an electronic document.